Androgen Receptor Expression in Locally Advanced Breast Cancer Predicts Lack of Pathological Complete Response After Neoadjuvant Treatment

Background: Data regarding the prognostic value of androgen receptor (AR) expression in locally advanced breast cancer (LABC) is limited. We aimed to determine the pathological complete response, defined as ypT0/is and ypN0, in a group of patients with AR-positive breast cancer after preoperative treatment. Methods: We evaluated immunohistochemical AR expression in 40 patients treated in our referral center. Univariate and multivariate models were used to assess the association between AR expression and pathological complete response (pCR). Results: AR expression varied from 75% in estrogen receptor-positive tumors to 11.7% in triple-negative tumors (P < 0.001). Three patients with AR-positive tumors achieved pCR. In the univariate model, AR expression was significantly associated with the absence of pCR (OR = 0.18; 95% CI, 0.04–0.75; P = 0.023). After adjusting for intrinsic breast cancer subtypes, AR-positive tumors had less probability of achieving a pCR compared with AR-negative ones (OR = 12.33; P = 0.046). Conclusions: AR expression was negatively correlated with pCR in our subset of patients with LABC who underwent neoadjuvant chemotherapy.